Treponema pallidum Flashcards
What are the two broad categories of serologic tests for Syphilis?
Non-treponemal and Treponemal
Which of the two types of serologic tests for syphilis test for a cardiolipin-cholesterol-lecithin antigen?
Non-treponemal
What percentage of non-treponemal test may have a false negative when they first present with chancre?
20-30%
What are the non-treponemal tests?
Rapid Plasma Reagin (RPR) Venereal Disease Research Laboratory (VDRL) Toluidine Red Unheated Serum Test (TRUST)
What are the Treponemal serologic tests?
Fluorescent Treponemal antibody absorption (FTA-ABS) Microhemagglutination test for antibodies to T. pallidum (MHA-TP) T. pallidum particle agglutination assay (TPPA) T. pallidum enzyme immunoassay (TP-EIA) Chemiluminescene immunoassay (CIA)
Which Treponemal test has become the favored test in laboratories with large numbers of specimens to test?
T. pallidum enzyme immunoassay (TP-EIA)
Can the spirochete Treponema pallidum be cultured?
no
When are people with venereal syphilis most infectious?
during primary and secondary stages of the disease, when moist, mucocutaneous lesions are present *persons with early syphilis may also be infectious
What are the three subdivisions of tertiary syphilis?
neurosyphilis cardiovascular syphilis gummatous syphilis
what are some differential diagnosis of primary syphilis?
chancroid lymphogranuloma vernereum granuloma inguinale codylomata acuminata herpes simplex carcinoma
What are some differential diagnosis of secondary syphilis?
pityriasis rosea drug eruption psoriasis lichen planus viral exanthema Stevens-Johnson syndrome
What is the first line treatment of syphilis?
Penicillin G benzathine 2.4 million units IM x 1 dose
What is the treatment for syphilis in patients allergic to PCN?
Doxycycline 100mg BID x 2 weeks
What is the median incubation period before chancre appears in primary syphilis?
21 days (range 3-90 days)
How long will the chancre of primary syphilis typically take to heal without treatment?
six weeks
After the a syphilis chancre heals, what percentage of patients will experience the systemic illness that represents secondary syphilis?
25%
What are the classic characteristics of the rash of secondary syphilis?
diffuse symmetric macular or papular eruption involving the entire trunk and extremities including the palms and soles
What term describes the large raised, gray to white lesions that may develop in warm, moist areas such as the mouth and perineum of patients with secondary syphilis?
condyloma lata
picture of secondary syphilis rash on palms
picture of secondary syphilis on trunk
picture of condyloma lata
